PB2452: PREVALENCE AND SEVERITY OF COVID-19 IN ALLOGENEIC HEMATOPOIETIC STEM CELL TRANSPLANTATION PATIENTS IN CHINA
Authors: Hongye Gao, Jiali Wang, Xinhui Zheng, Yigeng Cao, Aiming Pang, Erlie Jiang
Journal: HemaSphere (2023)

Topic: 22. Stem cell transplantation - Clinical Background: The ongoing Corona Virus Disease-2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has affected millions of people and caused tremendous health effects worldwide. There are greater concerns for immunocompromised patients, particularly those who have undergone allogeneic hematopoietic stem cell transplantation (HSCT). An estimated 30-day mortality of approximately 32% after COVID-19 diagnosis has been reported previously. The modified management of COVID-19 in mainland China, which started in December 2022, has introduced several challenges for the healthcare system. However, there is limited epidemiological data for these patients in China. Aims: To investigate the epidemiology and outcomes of COVID-19 in HSCT patients at the Institute of Hematology & Blood Diseases Hospital, Tianjin, China. Methods: To investigate the epidemiology and outcomes of COVID-19 in HSCT patients at the Institute of Hematology & Blood Diseases Hospital, Tianjin, China. Results: A total of 302 patients, with a median age of 38 years and male-to-female ratio of 1:1, were enrolled. Most of the patients underwent haploidentical HSCT (Table 1). A subset of COVID-negative samples was also tested for serum SARS-CoV-2 antibodies. HSCT patients had significantly lower IgG and IgM levels compared to healthy controls (P < 0.001). However, the pre-infection IgG levels did not correlate with disease severity in HSCT patients (Figure 1). During the study period, 218 patients (72.7%) developed a COVID-19 infection, with asymptomatic, mild, moderate, severe, and critical disease rates of 2%, 63.9%, 18.5%, and 3.4%, respectively. Seven (2.3%) patients had died by the last follow-up. All of them had received multiple prior treatments and/or prior transplantation. The median time from COVID-19 diagnosis to death was 15 days (range: 2–32 days). Summary/Conclusion: Initial serum IgG levels were unrelated to COVID-19 severity in HSCT patients. The proportion of severe disease and the mortality rate for COVID-19 in Tianjin were lower than those reported previously. However, there remains an urgent need for effective prevention and treatment strategies. Table 1. Baseline patient characteristics - Allogeneic hematopoietic stem cell transplantation n = 302 Age, y, (median [IQR]) 38.00 [29.00, 48.00] Male (%) 158 (52.3) CCI-index ≥ 2, n (%) 35 (11.6) ECOG ≥ 2 (%) 57 (18.9) Smoking history, n (%) 53 (17.5) Primary disease, n (%) ALL 175 (57.9) AML 81 (26.8) MDS 28 (9.3) Others* 18 (6.0) Donor matching, n (%) Haploidentical donor 160 (53.0) HLA-matched sibling 135 (44.7) Unrelated donor 7 (2.3) Time to HSCT, n (%) ≤ 6 months 142 (47.0) 6–12 months 30 (21.1) ≥ 12 months 130 (43.0) IQR: interquartile range; CCI: Charlson Comorbidity index (excluding primary disease); ECOG: Eastern Cooperative Oncology Group performance status; ALL: acute lymphocytic leukemia; AML: acute myeloid leukemia; MDS: myelodysplastic syndrome; HSCT: hematopoietic stem cell transplantation *lymphomas, multiple myeloma, aplastic anemia, chronic myelomonocytic leukemia, and mixed phenotype acute leukemia. Figure 1. Serum SARS-CoV-2 antibodiesSerum samples was tested using ELISA. IgG (A) and IgM (B) levels were significantly lower in COVID-negative HSCT patients (n = 15) than in healthy controls (n = 15). However, among the COVID-positive HSCT patients, there was no significant association between COVID-19 grade and IgG levels. Keywords: HSCT, Prevention, Prevalence, COVID-19